The oxidizer packets are a one-time use, although the mylar bags could possibly be cut down and reused. Cost of vacuum pump oil starts at $20 a gallon, although that oil can be filtered and reused. An oil-less pump is also an option but will be an upfront cost of
Specialty equipment serves a custom unique purpose. If you are planning on cooking something very specific, you may desire the exact tool for the job. This equipment might include pasta cookers, waffle cone makers, sous vide immersion circulators and more.
Be wary of buying freeze-dryers that come from locations where the unit could have been tampered with or damaged, even by accident.
Know what your personal preferences are to determine the efficacy of owning a home freeze-dryer. Trying out some commercially freeze-dried food might help in this quest.
Reinstalled the vacuum hose and capped far end of hose to do a hose test. (same results as pump alone)
On that point, I was first introduced to home freeze dryers while overseeing the guard force at the Embassy in Baghdad.
1) I installed a 3/4" wide high density closed cell foam in the gap between the front of the chamber and the back of the front panel - just what Harvest Right suggested except all the way around (the first picture shows the gap). Use your fingers to push it into place. It needs to be tight against the inside panel. I then installed a vapor barrier around the entire FDer chamber. I used 7mil plastic and clear packing tape.
Because the freezing is fast, relatively few cell walls are ruptured which means it can be rehydrated with much less loss of quality.
Oil Mist Filter: Both pumps come with an oil mist filter. However, the Premier Pump’s oil mist filter allows for no oil spray at all and it will last much longer.
When isolated, the pump seems to behave well. Short of putting a meter on the pump, my impression is that it is operating properly. I'm considering investing in a good meter to verify that it is reaching a good ultimate vacuum.
Moisture and temperature are the two critical factors in optimal food storage. Moisture - the humidity in the storage environment should be low. If dried foods pick up moisture from the storage area, molds and bacteria can grow. This can lead to spoilage
I did wonder though, since this is gravity flow and not pressure driven as on a car, if having the filter mounted horizontally might result in using only "half" the filter, as the oil would tend to travel through the low side of the filter -- although in practice, I suppose, as the filter material gets plugged it would force the fluid level higher.
Obviously things like ice cream and website marshmallows you would want to let the freeze cycle run longer. When I'm ready to start the drying cycle, I open the door, remove the insulator, and check the temperature of the food on the trays with an infrared thermometer. As long as it's below -10F I start the dry cycle. A side note for TonyC, have you ever thought about attaching a mirror to each side of the tray rack to reflect the radiant heat back in to the trays? I've looked at some mirror finish stainless on ebay, and it looks like you could do it for about $40. Not sure if it's worth a try or not. I would think it would let you get more water out in a cycle because the radiant heat wouldn't be warming the ice on the chamber walls. Just a thought.... Edited December 16, 2015 by Pipsqueak duplicate post (log)
I've run the system in countless tests including over filling the pump and running the pump without a load (both result in lots of oil spitting out the exhaust port of the pump). I've drained the catch can twice, once with over 5 oz of oil in it, but have not collected any oil downstream in the jar so the system is performing well.